extract common test setup
extract common test setup

DirtyHairy/6502.ts,6502ts/6502.ts,DirtyHairy/6502.ts,6502ts/6502.ts,DirtyHairy/6502.ts,DirtyHairy/6502.ts,6502ts/6502.ts,6502ts/6502.ts,6502ts/6502.ts